It's difficult to get a clear idea without all the accounts but as an off the cuff estimate, take the lottery funding at approx £2m and then the same again each year in cash / contributions and donations I would imagine.
Don't forget the value of the debt now secured on the aircraft to Mr Walton's business and to Marshalls for the purposes of calculation. I am sure someone has the numbers.....
Must be knocking on towards £11.5m so far. According to TVOC website t was £7m at return to flight and then 3 more years.
Call it a generous £11m for say 120 hours? £91,000 an hour....a snip.